Hey K,
thank you for your message. Due to tax reasons (FATCA), US expats have difficulties using brokers if they’re not in the US. That’s why I always recommend using a broker that is available in both the US and the country of residency (in your case, this will be an EU country later).
Because of this reason, Schwab seems a better option as it also accepts more non-US clients if you have a minimal account size ($25k+). If you click on “Open an account”, and select the preferred EU country, you can check if that’s available at Schwab: https://international.schwab.com/
In addition, Interactive Brokers (https://brokerchooser.com/broker-reviews/interactive-brokers-review) is a great option as it’s available in many countries globally.
Let me know if you have any questions.
Best,
Adam